Theoretical studies of step edge supersaturation and its [formula omitted] flux dependence in molecular beam epitaxy of GaAs on vicinal surfaces

Abstract

A theoretical growth model is developed for the dependence of the mode transition temperature on Ga and As fluxes in molecular beam epitaxy (MBE) of GaAs on (001) vicinal surfaces. The theoretical calculation shows that the transition temperature increases with the flux of either element. It is compared with experimental data reported by Shitara et al. [Crystal Properties and Preparation, Vols. 32–34 (Springer, Berlin, 1991) p. 332]. Analysis of the experimental results using our theory allows us to conclude that there is a strong anisotropy in the incorporation rates at the step edges and the incorporation rate is mainly determined by the AsGa flux ratio. The incorporation rate increases on the “B” surface misoriented towards [1̄10] with the increase of the flux ratio, while it shows little dependence on the flux ratio on the “A” surface misoriented towards [110].